Transducer beam assembly

ABSTRACT

For use on a vehicle which includes an axle and a spring, a load-measuring transducer assembly comprising first and second support members secured to the spring and the axle of a vehicle, respectively, in vertically spaced apart relationship, and an elongated beam having opposite ends disposed horizontally therebetween. A first fulcrum means is provided for pivotably, compressibly supporting the beam at the ends thereof in spaced apart relationship to the first member. A second fulcrum means for applying a flexing force to the beam in proportion to the load on the axle pivotably and compressibly supports the beam inwardly of the ends thereof in spaced apart relationship to the second support member. First and second coupling means pivotably couple the ends of the beam to the first member and the beam to the second member adjacent the second fulcrum means, respectively. A strain measuring means for measuring the flexing strain of the beam is mounted thereon.

United States Patent 1191 Videon TRANSDUCER BEAM ASSEMBLY [76] Inventor:John A. Videon, 1336 S.E. 38th Place, Gainesville, Fla. 32601 22 Filed:Sept. 22, 1972 211 Appl. No.: 291,327

Primary ExaminerGeorge 1-1. Mi11er, Jr. Attorney- Harold B. Hood, GeorgeA. Gust et al.

1451 July 3,1973

[57] ABSTRACT For use on a vehicle which includes an axle and a spring,a load-measuring transducer assembly comprising first and second supportmembers secured to the spring and the axle of a vehicle, respectively,in vertically spaced apart relationship, and an elongated beam havingopposite ends disposed horizontally therebetween. A first fulcrum meansis provided for pivotably, compressibly supporting the beam at the endsthereof in spaced apart relationship to the first member. A secondfulcrum means for applying a flexing force to the beam in proportion tothe load on the axle pivotably and compressibly supports the beaminwardly of the ends thereof in spaced apart relationship to the secondsupport member. First and second coupling means pivotably couple theends of the beam to the first member and the beam to the second memberadjacent the second fulcrum means, respectively. A strain measuringmeans for measuring the flexing strain of the beam is mounted thereon.

11 Claims, 7 Drawing Figures TRANSDUCER BEAM ASSEMBLY BACKGROUND OF THEINVENTION 1. Field of the Invention The present invention relates toload-measuring devices and in particular to a beam-type transducerassembly adapted for installation between the spring and axle of avehicle such as a truck or semi-trailer for measuring the load on theaxle.

2. DESCRIPTION OF THE PRIOR ART Trucks such as large semi-trailer rigsare subject to numerous regulations regarding weight for the purpose oflimiting maximum weight, taxation, and the like. Further, to achievemaximum operating efficiencies, such trucks should be loaded as fully asallowable. Correspondingly, facilities must be provided for measuringthe gross weight of the vehicle. One method of weighing such vehicles isto provide a large scale capable of supporting the entire truck orportions thereof. Such scales are very expensive and special facilitiesmust be provided for their installation. Further, such a scale, by itsnature, is only capable of measuring the weight of a single vehicle at atime whereby, vehicles must frequently wait in line at available weighstations.

As an alternative, systems commonly referred to as on board weighingsystems have been proposed. Such weighing systems typically include adevice which is coupled to the axle of the vehicle, the device providinga signal or other indication indicative of a load on the individualaxles. Such a system is disclosed in my copending patent application,Ser. No. 803,285, filed Feb. 28, 1969.

SUMMARY OF THE INVENTION The present invention is an improvement in thislastmentioned type of system. Broadly, the transducer beam assembly ofthe present invention comprises first and second support members whichare secured in vertically spaced apart relationship to the spring andthe axle, respectively, of a vehicle such as a semi-trailer rig. Anelongated simple beam having opposite ends is positioned between thesupport members. A fulcrum means pivotably supports the beams at theends thereof in spaced apart relationship to the first member and asecond fulcrum means pivotably supports the beam inwardly of its ends inspaced apart relationship to the second member, the second fulcrum meansapplying a flexing force to the beam in proportion to the load on theaxle. First and second coupling means are provided for pivotablycoupling the beam at the ends thereof and at points adjacent the secondfulcrum means to the first and second support members, respectively. Atransducer device is coupled to the beam for providing an electricalsignal proportional to the deformation thereof.

It is therefore an object of the invention to provide an improvedtransducer beam assembly for use in an on-board" weighing system.

It is another object of the invention to provide such an assembly whichprovides substantially linear indication of load.

It is still another object of the invention to provide a transducerassembly which is also a load-carrying member in a vehicle suspension.

It is yet another object of the invention to provide such an assemblywhich utilizes low friction supports and fulcrum pins to effect lowfriction operation.

It is an object of the invention to provide a transducer assemblywherein the load-measuring element includes a simple beam.

It is yet another object of the invention to provide such an assemblywhich is exceptionally rugged and resistant to shock.

It is still another object of the invention to provide a transducerassembly which is substantially unaffected by changes in the positionand tire pressures of the vehicle and uneven road surfaces and the like.

Another object of the invention is to provide a transducer assemblywhich provides certifiable load measurements.

Still another object of the invention is to provide such an assemblywhich can be used in multiple groups to provide a direct reading of loadon individual axles and of the total vehicle weight.

Yet another object of the invention is to provide a transducer assebmlywhich provides direct reading of the weight at a remote location such asthe cab of the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS The above-mentioned and other featuresand objects of this invention and the manner of attaining them willbecome more apparent and the invention itself will best understood byreference to the following description of an embodiment of the inventiontaken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a fragmentary side plan view of a vehicle showing the springand axle thereof with the transducer assembly of the present inventioninstalled therewith;

FIG. 2 is a side plan view of the transducer assembly;

FIG. 3 is an end plan view of the transducer assembly partially cut awayto show details of the coupling means;

FIG. 4 is an exploded perspective view of the transducer assembly;

FIG. 5 is a perspective view of the beam element of the transducerassembly;

FIG. 6 is an electrical schematic of a typical electrical circuit foruse with the transducer assembly of the present invention; and

FIG. 7 is a diagram useful in explaining the operation of the transducerassembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawingsthere is shown in FIG. 1 a portion of a vehicle 10 which includes asupporting frame 12, springs 14, axle 16, and a wheel and tire l8.Transducer beam assembly 20 is mounted between springs 14 and axle 16.

Transducer assembly 20 includes first and second support members 22, 24,which are fixedly secured to the spring 14 and axle 16, respectively.Support member 22 includes a rectangular base plate 26 of substantialthickness having secured thereto, as by welding, two upwardly (as viewedin the drawings) reinforcing walls 28, 30. Walls 28, 30 are taperedadjacent their ends as shown and are disposed in parallel relationshipand laterally spaced apart by dimension which permits spring 14 to beengageably received therebetween. A pair of threaded members 32, 34 arewelded to the outwardly disposed surfaces of walls 28, 30 with thedistal ends 36, 38 thereof extending upwardly of walls 28, 30. Arectangular clamping plate 40 is provided, plate 40 having a pair ofholes 42, 44 at the opposite ends thereof, holes 42, 44 dimensioned andspaced to receive therethrough members 36, 38. Threaded fasteners 46 arereceived on threaded members 36, 38 to thereby positively clamp supportmember 22 to the spring 14.

Second support member 24 includes upper and lower members 50, 52 (FIGS.2 and 3). Each of members 50, 52 has arcuately tapered ends as at 54 andan arcuate recess 56 (FIG. 4) adjacent the central portion thereofproportioned to engage the outer surface of axle 16. Holes 58 areprovided adjacent each corner of member 52, 54 with respectivevertically adjacent (as viewed in the drawings) ones of the holes inmembers 52 and 54, respectively, being disposed in axial alignment.

As best seen in FIGS. 4 and 5, an elastically bendable beam 60 havingopposite ends 62, 64 is positioned between support members 22, 24 inparallel, spaced-apart relationship to the facing surfaces 66, 68thereof, respectively. In the upper surface 70 of beam 60 adjacent ends62, 64 are formed elongated, arcuate recesses 72, 74, respectively,recesses 72, 74 extending laterally of the ends 62, 64. A second pair ofelongated, arcuate recesses 78, 80 are formed in the downwardly facing(as viewed in the drawings) surface 82 of beam 60, recesses 78, 80,being adjacent the ends 62, 64 and inwardly of recesses 72, 74.

Fulcrum pins 84, 86 each have a part-cylindrical cross-section and aflat surface 75 and are received with their arcuate surfaces in slidingengagement with recesses 72, 74, respectively, and surfaces 75abuttingly engage surface 66.

A second pair of fulcrum pins 88, 90 also having arcuate cross-sections'are received in recesses 78, 80 with their arcuate surfaces in slidingengagement therewith and with their flat surfaces 77 in abuttingengagement with surface 68.

Preferably, surfaces 66, 68 are provided with rectangular recesses as at91, 92 which engageably receive pins 84 through 90 to prevent movementthereof.

A plurality of cylindrical holes 96 are formed, one each, adjacent eachcorner of beam 60, holes 96 being aligned with the axes of recesses 7 2,74. The downward (as viewed in the drawings) ends of holes 96 areprovided with an enlarged, spherical shoulder as at 98 at the endsthereof proximal to surface 82. A second plurality of cylindrical holes100 are formed in beam 60 adjacent each end of recesses 78, 80 and inalignment therewith. The ends of holes 100 nearest surface 70 are againprovided with a spherical enlargement as at 102. A plurality ofelongated, threaded members 104, each of which is provided with ahemispherical head 106 as shown are slidably received through holes 100and 58 such that hemispherical heads 106 pivotably engage complementaryshoulders 102. Members 104 are secured by means of nuts 107. It will beobserved that members 104 and nuts 107 provide a means for positivelycoupling the beam 60 to support member 24.

A second plurality of threaded fasteners 110 are provided, each having ahexagonal head 112 and each head 112 in turn having a hemisphericalshoulder 114 as shown. Members 110 are slidably received through holes96 and threadingly engage a plurality of threaded holes 116 adjacent thecorners of support members 22 in registry with holes 96. It will beobserved that members 110 positively couple beam 60 to support member22.

As best seen in FIGS. 2 and 3, holes 96 and have a diameter larger thanthe diameters of members 104 and thereby providing clearancestherebetween as at 120, 122 for a reason to be explained below. It willalso be observed in FIGS. 4 and 5 that beam 60 has elongated notches124, 126 in its lateral edges whereby beam 60 has a smallercross-section through its central portion. This narrower cross-sectioneffects a beam which, when subjected to bending stress, will exhibitmore bending strain adjacent its center portion than at its ends.

Referring now to FIG. 7, there is shown diagrammatically the effect onthe beam 60 of a load carried by the axle 16. The load L bearsdownwardly on support member 22 (not shown in FIG. 7 for clarity) and issupported by the ends 62, 64 of beam 60 via pins 84, 86. Beam 60 is inturn supported on axle l6 and support member 24 via pins 88, 90. Becausepins 88, 90 are disposed inwardly of pins 84, 86 by a moment arm oflength a the load L produces a bending moment on the beam 60 causing thebeam 60 to bend as indicated by dashed lines 60a. Because pins 88, 90and 84, 86 are cylindrical and are supported within cylindrical recesses78, 80, 72, and 74, the length of the moment arms a remainssubstantially constant as beam 60 bends. Further, as the beam 60 bends,the clearances 120, 122 between members 104 and 110, respectively,enable the beam 60 to bend without imparting any bending moment to themembers 104, 110. Rather, the beam 60 pivots about the spherical heads106 and 114, respectively. Further, because the beam 60 is a simplebeam, the stress therein is substantially linear for small deflectionsthereof. correspondingly, the load L produces simple bending of beam 60which is substantially linear and wherein the only errors which occurresult from friction between the spherical heads 106, 114 of members104, 110, respectively, and the pins 88, 90, and 84, 86 with theirrespective recesses, these frictional forces being relativelyinsignificant in comparison to the bending moment caused by load L onthe beam 60.

Referring now to FIG. 6, there is illustrated an electrical circuitwhich may be used in conjunction with the transducer beam assembly abovedescribed to provide a means for measuring the strain or bendingmovement of the beam 60. A plurality of conventional strain gauges 130,132 are adhered to surfaces 70, 82 of beam 60 and adjacent the centerthereof in conventional manner, as shown in FIGS. 4 and 5. Gauges 130,132 are arranged in a bridge circuit, the bridge circuit including abalancing network 134 and being coupled to a source of alternatingoperating potential (not shown) via a coupling transformer 136. Theoutput from the strain gauges appearing at terminals 138, is applied tothe input terminals 142 of a linear amplifier 144 via resistors 146,148. Amplifier 144 is provided with conventional feedback resistor andcapacitors 152, 154. The output from amplifier 144 is in turn applied tothe input terminals 156 of a second linear amplifier 158 via loadresistors 160, 162. Amplifier 158 is provided with a variable feedbackresistance 164 and capacitors 166, 168 in conventional manner. Theoutput signal from amplifier 158 is applied via a transformer 170 to anoutput load including resistor 172 and capacitor 174, a suitable filtercapacitor 176 being coupled between the transformer 170 input winding178 and ground of reference potential 180. The output signal from thecircuit at terminal 182 can be applied to a conventional'digital oranalog meter (not shown). Additional transducer beam assemblies may bemounted to each of the axles of a vehicle, each of the additional unitsbeing of identical structure to that above described. The output signalsfrom the transducers of each of the assemblies can be summed via aconventional summing network (not shown) with the readout at the meteror the like (not shown) being the sum of the loads on each of the axlesand therefore equal to the entire load on the vehicle. The circuit ofFIG. 6 is shown by way of example only, it being obvious that anysuitable transducer circuit using resistance strain gauges or otheravailable strain-indicating devices may be used if lieu thereof.

It will be seen that the transducer assembly of the present inventionprovides an exceptionally rugged device for measuring the load on theindividual axles of a vehicle. The assembly can be mounted between theaxle and spring of such a vehicle without any need to weld, cut, orotherwise modify the vehicle. The sensitivity of the gauge can be easilyaltered to provide an assembly having different load ranges by simplychanging the dimension a between the two fulcrum means, and by varyingthe thickness and width dimensions of the beam 60. The beam 60, itself,is a simple beam with substantially all of the bending thereof occurringbetween the second fulcrum means whereby, for small defiections, thestrain occurring therein is directly proportional to the load on thevehicle.

The transducer assembly can be used in groups with one assemblyinstalled between the spring and the axle adjacent each wheel of thevehicle without any modification of the assembly, the total weight ofthe vehicle being the simple sum of the loads on each assembly. Theassembly is highly resistant to shock and, by reason of the arcuatefulcrum pins and pivot joints, is virtually unaffected by changes in thetire pressure, by reason of the vehicle resting on uneven terrain, andthe like.

While there have been described above the principles of this inventionin connection with specific apparatus, it is to be clearly understoodthat this description is made only by way of example and not as alimitation to the scope of the invention.

What is claimed is:

1. For use on a vehicle which includes an axle and a spring, aload-measuring transducer assembly comprising first and second supportmembers secured to the spring and the axle, respectively, of such avehicle in vertically spaced apart relationship, an elongated beamhaving opposite ends, first fulcrum means for pivotably and compressiblysupporting said beam at said ends thereof in spaced apart relationshipadjacent opposite ends of said first member, second fulcrum meanspivotably and compressibly supporting said beam inwardly of said endsand in spaced apart relationship adjacent opposite end of said secondsupport member for applying a bending force to said beam in proportionto the load on said axle, first coupling means for coupling said beamends to said first member for pivotal movement about a first axisextending laterally of said beam through said first fulcrum means,second coupling means for coupling said beam to said second member forpivotal movement about an axis extending laterally of said beam throughsaid second fulcrum means, and means coupled to said beam for measuringthe strain thereof.

2. The assembly of claim 1 wherein said first fulcrum means includes afirst pair of elongated pins of partcylindrical cross-section and arecess extending laterally of said beam adjacent each of said ends, eachof said first pair of pins being partially received in and slidablyengaging a respective one of said recesses, said second fulcrum meansincluding a second pair of elongated pins of part-cylindricalcross-section and a second pair of recesses in said beam, said secondrecesses extending parallel to said first recesses and being disposedinwardly thereof by a predetermined dimension, each of said second pairof pins being partially received in and slidably engaging a respectiveone of said second pair of recesses, the surfaces of said first andsecond fulcrum pins opposite said recesses abuttingly engaging the lowerand upper surfaces, respectively, of said first and second supportmembers.

3. The assembly of claim 2 wherein said pins each have a flat surfacedisposed diametrically opposite said recesses, said first and secondsupport members including recesses therein disposed in verticalalignment with said first and second recesses, respectively, andcomplementary to that portion of the surface of said pins including saidfiat surface, said first and second pins being partially received inrespective ones of said recesses with the flat surfaces thereof inabutting engagement with said first and second support members.

4. The assembly of claim 1 wherein said first coupling means includes apair of sockets in said beam disposed in alignment with each of saidfirst axes, a plurality of first coupling members each including asocketengaging portion, each said portion being pivotally received in arespective one of said sockets, each said first coupling member beingfixedly secured to said first support member, said second coupling meansincluding a pair of sockets in said beam disposed in alignment with eachof said second axes, a plurality of second coupling members eachincluding a socket-engaging portion, each of said last mentionedportions pivotally engaging a respective one of said last mentionedsockets, each said second coupling member being fixedly secured to saidsecond support member.

5. The assembly of claim 4 wherein said first sockets are hemisphericalrecesses in the surface of said beam distal said first member, therebeing a hole communicating between each of said hemispherical recessesand the surface of said beam proximal to said first member, each saidcoupling member being elongated and including a shaft portion and a headportion, said head portion having a hemispherical surface proximal tosaid shaft portion and complementary to said hemispherical recess, saidsecond sockets each including a hemispherical recess in the surface ofsaid beam distal said second member, there being other holescommunicating between each of said second hemispherical recesses and thesurface of said beam proximal said second member, said second couplingmembers being elongated and including a shaft portion and a headportion, said head portion having a hemispherical surface proximal tosaid shaft portion and complementary to said second hemisphericalrecess, said shaft portions extending through said last mentioned holesand being fixedly secured at the distal ends thereof to said secondmember.

6. The assembly of claim 5 wherein all of said holes and said shaftportions are cylindrical, said holes having a diameter greater than thediameter of said shaft portions, whereby, when said beam pivots aboutsaid sockets, said shaft portions move freely within said holes.

7. The assembly of claim 6 wherein said first support member includes arigid base plate and a pair of side walls fixedly secured thereto andextending vertically upwardly therefrom in parallel, spaced-apartrelationship, the lateral spacing of said walls being dimensioned toengageably receive said spring therebetween, and means for clamping saidfirst spring to said support member, said base plate and said beamextending generally horizontally in parallel, spaced-apart relationship.

8. The assembly of claim 7 wherein said second support member includesan upper and a lower member, said first and second members each havingan arcuate recess formed therein adjacent the centers thereof, said axlebeing engageably received between said first and second members withinsaid arcuate recesses.

9. The assembly of claim 8 wherein said first and sec- 0nd couplingmembers are elongated, the ends thereof distal said hemisphericalportions being threaded, said first coupling members extendingvertically upwardly through said first mentioned cylindrical holes, saidfirst support member including a threaded hole adjacent each cornerthereof in vertical registry with said first mentioned cylindricalholes, said threaded ends of said first coupling members beingthreadingly engaged therewith, said second .coupling members beingreceived vertically downwardly through said other holes, said first andsecond members having a cylindrical hole adjacent each corner thereof invertical registry with said other cylindrical holes, said secondcoupling members being slidably received therethrough, the distal endsof said second coupling members being threaded, a nut threadinglyreceived on the end of each of said other cylindrical members, whereby,said axle is clampingly engaged therebetween.

10. The assembly of claim 9 wherein there are two of said first couplingelements and two of said second coupling elements adjacent each end ofsaid beam.

11. The assembly of claim 10 wherein said transducer means includesresistance strain gauges mounted on said beam and further comprisingmeans coupled to said strain gauges for generating an electrical signalproportional to the change in resistance of said strain gauges.

UNITED STATES PATENT OFFICE QERTIFICATE OF CORRECTION Patent No. 3 qgoLDated Julv 3. 1973 Inventofls) John A. Videon It is certified that errorappears in the above-identified patent and that said Letters Patent arehereby corrected as shown below:

Col. 2, line 19, change "assebmly" to assembly,

Col. L line 66, change "of" to or Col 5, line 57', change "end" to endsSigned and sealed this 22nd day of January 1971;.

(SEAL) Attest:

EDWARD M. FLETCHERJR. RENE D. TEGTMEYER Attesting Officer ActingCommissioner of Patents UNITED STATES PATENT OFFICE QERTIFICATE OFCORRECTION Patent No. 7L6 OL l Dated JUlV 3 973 Inventor(g) John A.Videon It is certified that error appears in the above-identified patentand that said Letters Patent are hereby corrected as shown below:

C01. 2, line 19, change "assebmly" to assembly.

001. h, line 66, change "of" to or Col, 5, line 57, change "end" to endsSigned and sealed this 22nd day of January 197M.

( SEAL) Attest:

EDWARD M. FLETCHER, JR. RENE D. TEG'II JEYER Attesting Officer ActingCommissioner of Patents

1. For use on a vehicle which includes an axle and a spring, aload-measuring transducer assembly comprising first and second supportmembers secured to the spring and the axle, respectively, of such avehicle in vertically spaced apart relationship, an elongated beamhaving opposite ends, first fulcrum means for pivotably and compressiblysupporting said beam at said ends thereof in spaced apart relationshipadjacent opposite ends of said first member, second fulcrum meanspivotably and compressibly supporting said beam inwardly of said endsand in spaced apart relationship adjacent opposite end of said secondsupport member for applying a bending force to said beam in proportionto the load on said axle, first coupling means for coupling said beamends to said first member for pivotal movement about a first axisextending laterally of said beam through said first fulcrum means,second coupling means for coupling said beam to said second member forpivotal movement about an axis extending laterally of said beam throughsaid second fulcrum means, and means coupled to said beam for measuringthe strain thereof.
 2. The assembly of claim 1 wherein said firstfulcrum means includes a first pair of elongated pins ofpart-cylindrical cross-section and a recess extending laterally of saidbeam adjacent each of said ends, each of said first pair of pins beingpartially received in and slidably engaging a respective one of saidrecesses, said second fulcrum means including a second pair of elongatedpins of part-cylindrical cross-section and a second pair of recesses insaid beam, said second recesses extending parallel to said firstrecesses and being disposed inwardly thereof by a predetermineddimension, each of said second pair of pins being partially received inand slidably engaging a respective one of said second pair of recesses,the surfaces of said first and second fulcrum pins opposite saidrecesses abuttingly engaging the lower and upper surfaces, respectively,of said first and second support members.
 3. The assembly of claim 2wherein said pins each have a flat surface disposed diametricallyopposite said recesses, said first and second support members includingrecesses therein disposed in vertical alignment with said first andsecond recesses, respectively, and complementary to that portion of thesurface of said pins including said flat surface, said first and secondpins being partially received in respective ones of said recesses withthe flat surfaces thereof in abutting engagement with said first andsecond support members.
 4. The assembly of claim 1 wherein said firstcoupling means includes a pair of sockets in said beam disposed inalignment with each of said first axes, a plurality of first couplingmembers each including a socket-engaging portion, each said portionbeing pivotally received in a respective one of said sockets, each saidfirst coupling member being fixedly secured to said first supportmember, said second coupling mEans including a pair of sockets in saidbeam disposed in alignment with each of said second axes, a plurality ofsecond coupling members each including a socket-engaging portion, eachof said last mentioned portions pivotally engaging a respective one ofsaid last mentioned sockets, each said second coupling member beingfixedly secured to said second support member.
 5. The assembly of claim4 wherein said first sockets are hemispherical recesses in the surfaceof said beam distal said first member, there being a hole communicatingbetween each of said hemispherical recesses and the surface of said beamproximal to said first member, each said coupling member being elongatedand including a shaft portion and a head portion, said head portionhaving a hemispherical surface proximal to said shaft portion andcomplementary to said hemispherical recess, said second sockets eachincluding a hemispherical recess in the surface of said beam distal saidsecond member, there being other holes communicating between each ofsaid second hemispherical recesses and the surface of said beam proximalsaid second member, said second coupling members being elongated andincluding a shaft portion and a head portion, said head portion having ahemispherical surface proximal to said shaft portion and complementaryto said second hemispherical recess, said shaft portions extendingthrough said last mentioned holes and being fixedly secured at thedistal ends thereof to said second member.
 6. The assembly of claim 5wherein all of said holes and said shaft portions are cylindrical, saidholes having a diameter greater than the diameter of said shaftportions, whereby, when said beam pivots about said sockets, said shaftportions move freely within said holes.
 7. The assembly of claim 6wherein said first support member includes a rigid base plate and a pairof side walls fixedly secured thereto and extending vertically upwardlytherefrom in parallel, spaced-apart relationship, the lateral spacing ofsaid walls being dimensioned to engageably receive said springtherebetween, and means for clamping said first spring to said supportmember, said base plate and said beam extending generally horizontallyin parallel, spaced-apart relationship.
 8. The assembly of claim 7wherein said second support member includes an upper and a lower member,said first and second members each having an arcuate recess formedtherein adjacent the centers thereof, said axle being engageablyreceived between said first and second members within said arcuaterecesses.
 9. The assembly of claim 8 wherein said first and secondcoupling members are elongated, the ends thereof distal saidhemispherical portions being threaded, said first coupling membersextending vertically upwardly through said first mentioned cylindricalholes, said first support member including a threaded hole adjacent eachcorner thereof in vertical registry with said first mentionedcylindrical holes, said threaded ends of said first coupling membersbeing threadingly engaged therewith, said second coupling members beingreceived vertically downwardly through said other holes, said first andsecond members having a cylindrical hole adjacent each corner thereof invertical registry with said other cylindrical holes, said secondcoupling members being slidably received therethrough, the distal endsof said second coupling members being threaded, a nut threadinglyreceived on the end of each of said other cylindrical members, whereby,said axle is clampingly engaged therebetween.
 10. The assembly of claim9 wherein there are two of said first coupling elements and two of saidsecond coupling elements adjacent each end of said beam.
 11. Theassembly of claim 10 wherein said transducer means includes resistancestrain gauges mounted on said beam and further comprising means coupledto said strain gauges for generating an electrical signal proportionalto the change in resistance of said strain gauges.